Mechanism of cryorolling and aging treatment for enhancing corrosion properties of 2195 Al-Li alloy
(1. State Key Laboratory of Precision Manufacturing for Extreme Service Performance, Central South University, Changsha 410083, China;
2. Light Alloy Research Institute, Central South University, Changsha 410083, China;
3. Mark Wainwright Analytical Centre, University of New South Wales, Sydney, NSW 2052, Australia)
2. Light Alloy Research Institute, Central South University, Changsha 410083, China;
3. Mark Wainwright Analytical Centre, University of New South Wales, Sydney, NSW 2052, Australia)
Abstract: The impact of cryorolling (CR) and room temperature rolling (RTR) followed by artificial aging on the corrosion characteristics of 2195 Al-Li alloy (AA2195) was studied. Transmission electron microscope, scanning electron microscope, optical microscope, intergranular corrosion experiment, and electrochemical experiment were used. Throughout different stages of aging treatment, the corrosion behavior of both CR and RTR samples exhibited a sequential progression of pitting corrosion, followed by intergranular corrosion, and then pitting corrosion again. The corrosion rates of both samples initially showed an increase, followed by a gradual stabilization over time. The size and density of T1 phase significantly influenced the corrosion performance of the alloy. During the peak aging and over-aging stages, the CR sample exhibited superior corrosion resistance to the RTR sample, attributed to its finer T1 phase.
Key words: 2195 Al-Li alloy; cryorolling; aging treatment; corrosion performance